I have looked at the tuned port manifolds, both the aluminum and plastic ones, but there are too many things in different places for me to start over. I built a flow bench for the express purpose of trying to even out the internal flow characteristics of the stock manifold. If anyone is familiar with the Power Plate for the GN engines it looks like a tubular version of that, although not nearly as elegant looking. It seems to work as intended, at the devolopment test pressure of about 1/2 psi, or 14" of water, total flow through the manifold with the stock MAF and throttle body attached is a little over 300 cfm and total variation, high to low, between the individual ports is 1.2 cfm.
Both systems, turbo supercharging, or blower supercharging, have strengths and weaknesses, but I like the turbo'* ease of changing boost level in only a couple on minutes.